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		<title>three.js - WebGPU - Particles</title>
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		<div id="info">
			<a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> WebGPU - Particles
		</div>

		<script async src="https://unpkg.com/es-module-shims@1.3.6/dist/es-module-shims.js"></script>

		<script type="importmap">
			{
				"imports": {
					"three": "../build/three.module.js",
					"three/addons/": "./jsm/",
					"three/nodes": "./jsm/nodes/Nodes.js"
				}
			}
		</script>

		<script type="module">

			import * as THREE from 'three';
			import * as Nodes from 'three/nodes';

			import { GUI } from 'three/addons/libs/lil-gui.module.min.js';

			import { range, texture, mix, uv, mul, mod, rotateUV, color, max, min, div, clamp, positionWorld, invert, timerLocal } from 'three/nodes';

			import WebGPU from 'three/addons/capabilities/WebGPU.js';
			import WebGPURenderer from 'three/addons/renderers/webgpu/WebGPURenderer.js';

			import { OrbitControls } from 'three/addons/controls/OrbitControls.js';

			let camera, scene, renderer;
			let controls;

			init();

			function init() {

				if ( WebGPU.isAvailable() === false ) {

					document.body.appendChild( WebGPU.getErrorMessage() );

					throw new Error( 'No WebGPU support' );

				}

				const { innerWidth, innerHeight } = window;

				camera = new THREE.PerspectiveCamera( 60, innerWidth / innerHeight, 1, 5000 );
				camera.position.set( 1300, 500, 0 );

				scene = new THREE.Scene();
				//scene.fogNode = new Nodes.FogRangeNode( Nodes.color( 0x0000ff ), Nodes.float( 1500 ), Nodes.float( 2100 )  );

				// textures

				const textureLoader = new THREE.TextureLoader();
				const map = textureLoader.load( 'textures/opengameart/smoke1.png' );

				// create nodes

				const lifeRange = range( .1, 1 );
				const offsetRange = range( new THREE.Vector3( - 2, 3, - 2 ), new THREE.Vector3( 2, 5, 2 ) );

				const timer = timerLocal( .2, 1/*100000*/ ); // @TODO: need to work with 64-bit precision

				const lifeTime = mod( mul( timer, lifeRange ), 1 );
				const scaleRange = range( .3, 2 );
				const rotateRange = range( .1, 4 );

				const life = div( lifeTime, lifeRange );

				const fakeLightEffect = max( .2, invert( positionWorld.y ) );

				const textureNode = texture( map, rotateUV( uv(), mul( timer, rotateRange ) ) );

				const opacityNode = mul( textureNode.a, invert( life ) );

				const smokeColor = mix( color( 0x2c1501 ), color( 0x222222 ), clamp( mul( positionWorld.y, 3 ) ) );

				// create particles

				const smokeNodeMaterial = new Nodes.SpriteNodeMaterial();
				smokeNodeMaterial.colorNode = mul( mix( color( 0xf27d0c ), smokeColor, min( mul( life, 2.5 ), 1 ) ), fakeLightEffect );
				smokeNodeMaterial.opacityNode = opacityNode;
				smokeNodeMaterial.positionNode = mul( offsetRange, lifeTime );
				smokeNodeMaterial.scaleNode = mul( scaleRange, max( .3, lifeTime ) );
				smokeNodeMaterial.depthWrite = false;
				smokeNodeMaterial.transparent = true;

				const smokeInstancedSprite = new THREE.Mesh( new THREE.PlaneGeometry( 1, 1 ), smokeNodeMaterial );
				smokeInstancedSprite.scale.setScalar( 400 );
				smokeInstancedSprite.isInstancedMesh = true;
				smokeInstancedSprite.count = 2000;
				scene.add( smokeInstancedSprite );

				//

				const fireNodeMaterial = new Nodes.SpriteNodeMaterial();
				fireNodeMaterial.colorNode = mix( color( 0xb72f17 ), color( 0xb72f17 ), life );
				fireNodeMaterial.positionNode = mul( range( new THREE.Vector3( - 1, 1, - 1 ), new THREE.Vector3( 1, 2, 1 ) ), lifeTime );
				fireNodeMaterial.scaleNode = smokeNodeMaterial.scaleNode;
				fireNodeMaterial.opacityNode = opacityNode;
				fireNodeMaterial.blending = THREE.AdditiveBlending;
				fireNodeMaterial.transparent = true;
				fireNodeMaterial.depthWrite = false;

				const fireInstancedSprite = new THREE.Mesh( new THREE.PlaneGeometry( 1, 1 ), fireNodeMaterial );
				fireInstancedSprite.scale.setScalar( 400 );
				fireInstancedSprite.isInstancedMesh = true;
				fireInstancedSprite.count = 100;
				fireInstancedSprite.position.y = - 100;
				fireInstancedSprite.renderOrder = 1;
				scene.add( fireInstancedSprite );

				//

				const helper = new THREE.GridHelper( 3000, 40, 0x303030, 0x303030 );
				helper.material.colorNode = new Nodes.AttributeNode( 'color' );
				helper.position.y = - 75;
				scene.add( helper );

				//

				renderer = new WebGPURenderer();
				renderer.setPixelRatio( window.devicePixelRatio );
				renderer.setSize( window.innerWidth, window.innerHeight );
				renderer.setAnimationLoop( render );
				document.body.appendChild( renderer.domElement );

				//

				controls = new OrbitControls( camera, renderer.domElement );
				controls.maxDistance = 2700;
				controls.target.set( 0, 500, 0 );
				controls.update();

				//

				window.addEventListener( 'resize', onWindowResize );

				// gui

				const gui = new GUI();

				gui.add( timer, 'scale', 0, 1, 0.01 ).name( 'speed' );

			}

			function onWindowResize() {

				const { innerWidth, innerHeight } = window;

				camera.aspect = innerWidth / innerHeight;
				camera.updateProjectionMatrix();

				renderer.setSize( innerWidth, innerHeight );

			}

			function render() {

				renderer.render( scene, camera );

			}

		</script>
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